What is the impact of shingles on the heart, particularly in older adults with pre-existing cardiovascular disease?

Shingles and Cardiovascular Risk

Shingles (herpes zoster) significantly increases the risk of major cardiovascular events, including stroke and myocardial infarction, with the highest risk occurring 5-12 years after infection, and this risk is particularly concerning in older adults who already have high baseline cardiovascular disease prevalence.

Magnitude of Cardiovascular Risk

The cardiovascular impact of shingles is substantial and long-lasting:

• Patients with a history of shingles have a 38% increased risk of stroke at 5-8 years post-infection and a 28% increased risk at 9-12 years, compared to those without shingles 1
• For coronary heart disease, the risk increases by 16% at 5-8 years and 25% at 9-12 years after shingles 1
• The risk of venous thromboembolic events is elevated in the 60-90 days immediately following shingles 2
• These cardiovascular complications occur on top of the already high baseline risk in older adults, where 65-70% of those aged 60-79 and 79-86% of those ≥80 years already have cardiovascular disease 3

Mechanisms of Cardiac Involvement

Varicella-zoster virus causes direct cardiovascular complications through multiple mechanisms:

• The virus can cause inflammatory vasculopathy affecting blood vessels, leading to both hemorrhagic and ischemic complications 4
• Direct cardiac involvement includes pleuropericarditis that can simulate acute myocardial infarction and complete heart block 5
• VZV reactivation involves multiple foci in sensory and autonomic ganglia, which can result in co-incident activation affecting cardiovascular structures 5
• The inflammatory response triggered by viral reactivation contributes to atherosclerotic plaque destabilization and thrombotic events 4

Critical Clinical Implications for Older Adults

The intersection of shingles and pre-existing cardiovascular disease in older adults creates a particularly high-risk scenario:

• Older adults ≥75 years already experience 35-40% of incident MIs and up to 60% of MI-related deaths, despite representing only 6% of the population 6
• Approximately 70% of adults aged 75 years or older have hypertension, the most prevalent modifiable cardiovascular risk factor 3, 7
• Older patients with coronary disease have more extensive atherosclerosis with higher prevalence of prior MI, multi-vessel disease, and left main coronary artery obstruction 6
• The addition of shingles-related inflammatory vasculopathy to this already compromised cardiovascular system substantially amplifies risk 4

Prevention and Treatment Strategies

Antiviral treatment and vaccination are critical interventions that reduce cardiovascular risk:

• Treatment with antiviral agents within ±7 days of shingles diagnosis reduces cardiovascular event risk by 18% (adjusted hazard ratio 0.82) 8
• Statin therapy during the acute shingles period reduces cardiovascular risk by 29% (adjusted hazard ratio 0.71) 8
• The Shingrix vaccine demonstrates 50% effectiveness in preventing shingles among patients with inflammatory arthritis on immunosuppressive therapy 2
• The American College of Rheumatology strongly recommends vaccination against herpes zoster in patients aged ≥18 years taking immunosuppressive medications 2

Key treatment principles:

• Initiate antiviral therapy immediately upon diagnosis of shingles, ideally within 72 hours but benefits extend to ±7 days 8
• Continue or initiate statin therapy during acute shingles, as this provides independent cardiovascular protection 8
• Ensure patients receive both doses of Shingrix vaccine, as only 73.2% of those receiving a first dose complete the series 2
• The second Shingrix dose should be administered within 2-6 months after the first dose 2

High-Risk Period Monitoring

Cardiovascular surveillance should be intensified during specific post-shingles timeframes:

• The 5-12 year period after shingles represents the highest risk window for stroke and coronary events 1
• Venous thromboembolic risk is elevated specifically in the 60-90 day period immediately following shingles 2
• During these high-risk periods, optimize evidence-based cardiovascular medications including antiplatelet agents, antihypertensives, and statins 3, 9
• Blood pressure control is particularly critical, as it reduces fatal stroke by 39% and all-cause mortality by 21% in adults ≥80 years 9

Diagnostic Considerations

Clinicians must maintain heightened suspicion for cardiovascular complications in older adults with recent or active shingles:

• Chest pain in the setting of acute or recent shingles may represent pleuropericarditis, myocardial infarction, or both 5
• ST elevation on ECG during shingles requires differentiation between viral pericarditis and acute coronary syndrome 5
• New heart block in the context of shingles should prompt consideration of VZV-related cardiac conduction system involvement 5
• Older adults often present with atypical symptoms—only 40% of patients ≥85 years present with chest pain during acute coronary syndrome, compared to 77% of those <65 years 6

Prevention as Primary Strategy

Given the long-term cardiovascular implications, preventing shingles through vaccination is paramount:

• Vaccination reduces the incidence of shingles and consequently lowers the risk of subsequent cardiovascular events 4, 2
• This is especially important because preventing shingles substantially reduces quality of life deterioration and medical costs 4
• Active vaccination is recommended for high-risk groups, particularly older adults with pre-existing cardiovascular disease 4
• The cardiovascular protective effect of preventing shingles adds to the established benefits of avoiding postherpetic neuralgia and other neurological complications 4